Bob,
Sorry I skipped your post. It looks like you will need to move F1 back to accommodate the extra length. I would make it bigger to account for the difference in fuselage size at that location. Here is a link to a picture of mine
http://www.rcuniverse.com/forum/atta...5&d=1375575992 If you decide to leave it where it is and fill in with extra balsa, you would have to run a smaller spinner and make sure you don't go over 2m in overall length.
Jeff